Disease Control

Botrystop

BioWorks Product Logo

EPA REGISTERED & OMRI Listed

BotryStop® Organic Fungicide is an effective biological fungicide developed specifically for the control of pathogens such as botrytiscinerea, sclerotinia sclerotiorum and monilinia spp. It is based on the naturally occurring non-pathogenic saprophytic fungus ulocladium oudemansii (Strain U3) and provides protection to blossoms, fruit and plant tissue.

BotryStop utilizes ulocladium oudemansii (Strain U3), a novel new biological weapon and approach to organically fight tough diseases. When BotryStop spores are deposited on the dead and senescent plant debris they germinate and colonize. The developing mycelia proceed to colonize dead tissue and additional sporulation can occur. These new spores are then available to colonize remaining plant debris. BotryStop aggressively occupies the same physical space and out-competes pathogens for the nutrients in dead and senescing plant tissue.

BotryStop Benefits

• Water-dispersible granular formulation.
• Excellent tool for resistance management.
• Tank-mix compatible with some chemical inputs.
• Control as good as a full-season chemical program can be achieved with a BotryStop program.
• OMRI Listed for organic production.
• Exempt from residue tolerance.
• Use at or before the first sign of disease.
• 4-hour REI, 0-day PH.

BotryStop is organic and environmentally-friendly, can be used for a
wide array of tough to cure diseases and is safe for pets, animals and children.

BotryStop is Labeled for the Following Diseases

BotryStop Fungicide can be applied to a wide variety of field, greenhouse and high-tunnel grown trees, vegetables*, grapes and other small fruits. It can also be applied to ornamentals in greenhouses and nurseries. It is NOT labeled for use on vegetables and for certain diseases in California. Please see label for details and check with your local laws to ensure this product can be used in your area.

  • Gray Mold
  • Brown Rot Blossom Blight
  • Jacket Rot
  • Green Fruit Rot
  • Botrytis Blight
  • Mummy Berry*
  • Botrytis Leaf Blight*
    ...See label for full list of diseases
  • Botrytis Neck Rot
  • Sclerotinia Head and Leaf Drop*
  • Stem Rot
  • Erwinia amylovora
  • Sclerotinia sclerotiorum
  • Jacket Rot
  • Green Fruit Rot
  • Fire Blight*

*Not labeled for use in California.

BotryStop General Treatment

General Application: Apply BotryStop at a range of 2-4 lbs. per acre. The most common rate is 3 lbs. per acre.
Powdery Mildew: To cure powdery mildew, apply up to the maximum rate (5 lbs. per acre) every week for three weeks.

  • Do not exceed 2.0 tbsp. per gallon of water per week (equivalent to 5 lbs. per acre per week.)
  • Shorten the interval during rainy weather or during periods of high relative humidity.
  • Use sufficient water volume to provide complete coverage and wetting of plants.
  • A non-ionic surfactant or spreader sticker must be used when making applications.
  • Use of organosilicone surfactants is beneficial when spraying low water volumes (below 50 gallons per acre). Do not use organosilicone surfactants that claim to be “penetrants” or “stomatal flooders or infiltrators”.
  • Ensure constant agitation throughout the loading, mixing and application operations.
  • Multiple applications may be needed depending on crop and disease pressure.

For BotryStop Compatibility Chart Click Here.

BotryStop Active Ingredient

Ulocladium oudemansii (Strain U3) ................................................... 45%*.
*Contains not less than 8 x 107 cfu/gram.

BotryStop Available Sizes

12 lb. Bag (Covers 4 acres on average).

Sign up for our mailing list for product updates and best practices. Plus, receive special offers and reminders about when to order and apply.


By submitting this form, you are consenting to receive marketing emails from: . You can revoke your consent to receive emails at any time by using the SafeUnsubscribe® link, found at the bottom of every email. Emails are serviced by Constant Contact